1. Field of the Invention
The present invention relates to a connector.
2. Description of the Related Art
Japanese Unexamined Patent Publication No. 2000-150069 discloses a lock arm structure for holding connectors in a connected state. This structure includes a lock arm supported resiliently on the outer surface of a housing via a coupling portion. The coupling is long in forward and backward directions and is deformed resiliently with displacement of the lock arm. The long coupling advantageously prevents breakage since stress on the coupling is distributed more easily when the lock arm is displaced relative to the outer surface of the housing.
However, a long flow path for resin exists when the coupling is longer, and a filling efficiency of resin during injection molding of the coupling is reduced. Resin filling efficiency could be improved by shortening the coupling and connecting the lock arm to protection walls at the opposite left and right sides of the lock arm. Thus the lock arm is displaced like a seesaw by torsionally deforming the connections to the protection walls. Two curved surfaces may be provided at the opposite front and rear sides of each connection to the protection walls and curves may be provided at the opposite upper and lower corners of each curved surface to alleviate stress in a torsional direction to prevent breakage of the connections. Forming the curves over the entire corner portions of the curved surfaces requires a slide structure and leads to a cost increase of a shaping die.
The present invention was completed in view of the above situation and an object thereof is to provide curved portions over substantially the entire corner portions of curved surfaces of a coupling portion without providing a slide structure.